Light-sensitive silver halide photographic materials are usually photographically processed using processing solutions such as a black and white developing solution, a fixing solution, e color developing solution, a bleaching solution, a bleach-fixing solution and a stabilizing solution to give an imagewise reproduction. The respective processing solutions used here are each put into a plastic bottle or bottles in the form of a single or plural parts of liquid concentrates, and supplied to users as processing chemical kits. When used, users dilute these processing chemical kits with water to prepare service solutions (starting solutions or replenishing solutions).
In recent years, in the photographic processing business, there is a rapid increase in small-scale photofinishing laboratories called mini-labs. With a wide spread of such mini-labs, the quantity of use of processing chemical kit plastic bottles is rapidly increasing year by year.
Plastics used therefor are also widely used for articles other than photographic processing chemical kit bottles because of their light and tough properties. The production of plastics throughout the world is steadily increasing year by year, and has increased to an amount more than one hundred million in metric tons the year 1988. On the other band, waste plastic materials are also in an enormous amount. Taking an example in Japan, about 40% of the whole production is disposed of every year. Such waste plastic materials, when thrown away in the ocean, cause pollution of the environment for orceanic life. In the area of Europe, waste plastic materials are burned in incinerators having imperfect exhaust-gas disposal equipment to cause the problem of acid rain or the like, which has become an important subject of discussion.
For this reason, prompt countermeasures are earnestly sought to be taken. Under existing circumstances, it is active in Europe and America to recycle waste plastic materials or prohibit their dumping, or legally obligate to use degradable plastics.
Under such circumstances, it is very unpreferable to use plastic bottles in a large quantity for photographic processing chemicals even if their use is a part of the whole.
Now, one may contemplate to form liquid concentrates into powdered chemicals. In such an instance, there is a high possibility that fine powder rises or flies up when the powdered chemicals are dissolved in water and operators breathe the powder. This may bring about the problem of a possible influence on health, or the problem that any components of the processing chemicals that have flown about mix into other photographic processing solutions to contaminate them to cause troubles. On account of such problems, for example, Japanese Patent Publication Open to Public Inspections (hereinafter "Japanese Patent O.P.I. Publication(s)") No. 109042/1990 and No. 109043/1990, U.S. Pat. No. 2,843,484, Japanese Patent O.P.I. Publication No. 39735/1991 have proposed techniques in which photographic processing chemicals are formed into granules to give a granular mixture. However, there still remain the problem on labor safety and sanitation, caused by dust of flying chemicals, and the problems of difficulties in preparation operability such that the flying chemicals mix into other photographic processing solutions as impurities, caking may occur which is a phenomenon in which processing chemicals settle down to the bottom of a container and coagulate there when dissolved, and the powder may be covered with its own wet films to cause a poor dissolution. Thus, under existing circumstances, the scope of chemicals suited for being formed into powder of granules is very limited.
Now, it is proposed in Japanese Patent O.P.I. Publication No. 61837/1976 to form processing chemicals into tablets as a form preferable for processing chemicals making the most of the advantages attainable when they are in a dried state.
However, laminating at tableting (cracking of a tablet in the lateral direction) has occurred when the photographic processing chemicals are formed into granules, so that they cannot be well formed into tablets, bringing about a problem. Polyethylene glycol commonly used as a binder for tablets of medical use is an undesirable binder since, when used in developers, it adversely affects photographic performance and becomes inactive. Now, it is desired to newly provide a binder that does not affect photographic performances.
Besides, in the case of the liquid concentrate types, incorporation of an acid, an alkali or a pH adjuster which are components of processing chemicals may bring about additional problems such that the processing chemical components contained in liquid concentrates cause a chemical reaction to form a precipitate, they can not be added in a large quantity because of restriction in solubility, and, if a liquid solvent is added, various organic compound components contained may dissolve to undergo oxidation deterioration, resulting in decomposition of the components. As for the solid types such as powder, granules and tablets, they have difficulty in dissolving performance as previously stated, which is caused by a slightly water-soluble organic compound incorporated as a component of processing chemicals. Hence, it becomes often impossible to add the slightly water-soluble organic compound that is a processing chemical component important for photographic performance. Thus, it has been sought to establish a technique for incorporating such a slightly water-soluble organic compound into the solid type processing chemicals.